The Radio and Records Magazine is the place.
Most country music stations in the USA are programed by two programming services. If they pull the Dixie chick Records that leaves only the big market high power stations to play their records. A firm in Cleveland Ohio programs several large country music power houses, if they pull their records they will be off the charts. They may never get back on them.
AS far as station's thinking they can get publicity by playing their records, people in their audience area should call local sponsors and tell them they will boycott their firm as long as they advertise on the station playing Dixie Chick records. All it takes is a sponsor or two calling the station saying pull my spots or the Dixie Chicks records... your choice, the Chicks will be history.